hi working with AT89C51ED2 device from Atmel, has anyone encountered a situation in which a single or multiple bit of the internal flash image file get corrupted? i need a few hints on this phenomena which prevent correct code execution, major suspicion is brown-out scenario? Best regards
Do you have a reset supervisor, if not you will occasionally lose the flash. RC reset is NOT sufficient for flash based devices.
Erik
hi thanks for all the answers, just to clarify more, i currently have a external POR device, one thing i think of is that it can get into contention with the internal POR/WDT/PFD circuits that drive reset out if asserted. Guy.
I'm having similar problems with an 89C51RC2. I occassionally get the first 128 bytes of flash set to FF. I have no power supply supervisor. Is it likely that an entire half page of memory gets corrupted by a brownout. I don't seem to be able to replicate this on the bench but I have had equipment returned with 'dead' processors which have this fault.
Has the original poster resolved his issue?
i currently have a external POR device, one thing i think of is that it can get into contention with the internal POR/WDT/PFD circuits that drive reset out if asserted. when using "a external POR device"ith a chip that has "internal POR/WDT/PFD circuits that drive reset out" it is essential not to use a push-pul output supervisor.
I'm having similar problems with an 89C51RC2. I occassionally get the first 128 bytes of flash set to FF. I have no power supply supervisor. then add one (see note above)
hi i haven't resolved this issue yet, another solution to the internal POR contention with the external POR is inserting a series resistor/DIODE between the external Reset pin of the POR device and the reset pin of the 8051. as suggested in the 8051 HW design guide. BR guy